Apparatus and method for providing mobile iptv service in mobile communication system and broadcasting system

ABSTRACT

In a mobile communication system and a broadcasting system, an Advanced Base Station (ABS) periodically broadcasts a buffering data packet of broadcast buffering content in providing a Mobile Internet Protocol TeleVision (Mobile IPTV) service. The broadcast buffering content represents content in which a buffering data packet corresponding to a predetermined buffering capacity is periodically broadcasted, and the buffering data packet represents a data packet that is transmitted to be buffered in advance before the broadcast buffering content is actually provided to Advanced Mobile Stations (AMSs).

CLAIM OF PRIORITY

This application is a divisional application of U.S. patent applicationSer. No. 13/104,237 filed on May 10, 2011 and claims the benefit under35 U.S.C. §119(a) of a Korean Patent Application filed in the KoreanIntellectual Property Office on May 11, 2010 and assigned Serial No.10-2010-0043983, the entire disclosure of which is hereby incorporatedby reference.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to an apparatus and method for providing aMobile Internet Protocol TeleVision (Mobile IPTV) service in a mobilecommunication system and a broadcasting system.

2. Description of the Related Art

Wired IPTV systems provide real-time broadcast services andVideo-on-Demand (VoD) services. The real-time broadcast services areprovided using a plurality of real-time broadcast channels. When channelswitching is made from the current real-time broadcast channel to a newreal-time broadcast channel, a few seconds are required to receive datapackets provided over the new real-time broadcast channel and decode thereceived data packets, causing a delay in the channel switching. Manydifferent ways to minimize the switching time required for switchingbetween real-time broadcast channels have been proposed, and a detaileddescription thereof will be made below.

Data packets being provided in real-time broadcast channels, such asadjacent real-time broadcast channels like the real-time broadcastchannels whose channel numbers are just above and below a channel numberof the current real-time broadcast channel presently providing areal-time broadcast service, or real-time broadcast channels whosechannel numbers include a channel number corresponding to a specificnumber on a remote controller, which has been pushed by a user, arereceived in advance and then buffered. Thereafter, if channel switchingis made from the current real-time broadcast channel to a new real-timebroadcast channel, one of the adjacent real-time broadcast channels, thereal-time broadcast channels may be switched without the switchingdelay.

In order to switch real-time broadcast channels without switching delayfor all real-time broadcast channels, including the real-time broadcastchannels whose channel numbers are just above and below a channel numberof the current real-time broadcast channel, data packets correspondingto a predetermined buffering capacity should be received in advance andthen buffered, for all the real-time broadcast channels provided by thewired IPTV systems.

As for the real-time broadcast channels, because data packets beingprovided over them may be decoded in advance through increases inhardware and computations of receivers, the switching time required forswitching between the real-time broadcast channels is relatively short.However, in case of the VoD services, because the number of theiravailable content channels is much greater than the number of real-timebroadcast channels and it is difficult to predict which content channela user will select, the time period required between the time the userselected a specific content channel and the time the specific contentchannel actually starts playing the content, is relatively long.

In the wired IPTV systems, in order to reduce the switching timerequired for switching between content channels, data packets beingprovided in content channels having a high correlation with the contentbeing played in the current content channel are buffered in advance, andif new content channels, whose data packets have been buffered inadvance, are selected, the data packets having been buffered are playedimmediately. This method will be described below with reference to FIG.1.

FIG. 1 schematically illustrates a process of playing content uponswitching of content channels in a general wired IPTV system.

The process, illustrated in FIG. 1, of playing content channels uponswitching of content channels is a content playing process, in which forexample, the content being played in the current content channel is alive baseball game in which a specific baseball player called ‘LionKing’ takes part, and channel switching is made to a content channelhaving a high correlation with the live baseball game, i.e., a newcontent channel in which videos of previous games, where the specificbaseball player participated in, are played.

Referring to FIG. 1, while the current content channel plays a livebaseball game of the specific baseball player, content having a highcorrelation with the content being played in the current contentchannel, for example, data packets provided in new content channelsproviding videos of previous games of the specific baseball player arebuffered in advance.

As illustrated in FIG. 1, correlations between content being played inthe current content channel and content to be played in the new contentchannels should be managed in a hierarchical manner to enable channelswitching from the current content channel to the new content channels.However, in order to manage correlations between contents in ahierarchical manner, a database for the correlations between contentsshould be built, and additional overhead is required, such astransmission/reception of the correlation information.

Unlike the content channel switching method described in FIG. 1, a newmethod has been proposed, which switches content channels by bufferingin advance data packets provided in new content channels existing inupper/lower tree menus of the menu in which the current content channelis included, using the characteristics that in case of VoD services,content thereof is likely to be selected according to the given menus.

Although the above-described real-time broadcast channel switchingmethod and content channel switching method may reduce the switchingtime, unicast transmission or multicast transmission for transmittingdata packets each user terminal will buffer in advance for the reductionin the switching time may continue to occur.

This continuous unicast transmission or multicast transmission is not abig problem in the wired environments where the sufficient transmissionbandwidth and sufficient transfer rate may be guaranteed, like in thewired IPTV systems, so the real-time broadcast channel switching methodand content channel switching method, in which the unicast transmissionor multicast transmission continues to occur, may be used in the wiredIPTV systems without significant problems.

However, if the real-time broadcast channel switching method and contentchannel switching method used in the wired IPTV systems are used in thewireless environments where the communication capacity and transmissionbandwidth are limited, like in Mobile IPTV systems, use of which hasbeen greatly increased recently, then the number of user terminals towhich a Mobile IPTV service can be provided by the Mobile IPTV systemsis limited due to an increase in the unicast transmission.

Therefore, the real-time broadcast channel switching method and contentchannel switching method used in the wired IPTV systems can hardly beused intact in the Mobile IPTV systems, leading to the necessity for anew real-time broadcast channel switching method and content channelswitching method capable of minimizing the switching time.

SUMMARY OF THE INVENTION

An aspect of the present invention is to address at least theabove-mentioned problems and/or disadvantages and to provide at leastthe advantages described below. Accordingly, an aspect of the presentinvention provides an apparatus and method for providing a Mobile IPTVservice in a mobile communication system and a broadcasting system.

Another aspect of the present invention provides a Mobile IPTV servicedelivery apparatus and method for minimizing a switching time in amobile communication system and a broadcasting system.

Further another aspect of the present invention provides a Mobile IPTVservice delivery apparatus and method for minimizing a ratio of unicasttransmission in a mobile communication system and a broadcasting system.

Yet another aspect of the present invention provides an apparatus andmethod for providing a Mobile IPTV service using a broadcast network anda mobile communication network together in a mobile communication systemand a broadcasting system.

In accordance with one aspect of the present invention, there isprovided a method for providing a Mobile Internet Protocol TeleVision(Mobile IPTV) service by an Advanced Base Station (ABS) in a mobilecommunication system and a broadcasting system. The method includesperiodically broadcasting a buffering data packet of broadcast bufferingcontent. The broadcast buffering content represents content in which abuffering data packet corresponding to a predetermined bufferingcapacity is periodically broadcasted, and the buffering data packetrepresents a data packet that is transmitted to be buffered in advancebefore the broadcast buffering content is actually provided to AdvancedMobile Stations (AMSs).

In accordance with another aspect of the present invention, there isprovided a method for providing a Mobile IPTV service by an AdvancedMobile Station (AMS) in a mobile communication system. The methodincludes receiving a buffering data packet of broadcast bufferingcontent, which is periodically broadcasted. The broadcast bufferingcontent represents content in which a buffering data packetcorresponding to a predetermined buffering capacity is periodicallybroadcasted, and the buffering data packet represents a data packet thatis transmitted to be buffered in advance before the broadcast bufferingcontent is actually provided to AMSs.

In accordance with another aspect of the present invention, there isprovided an Advanced Base Station (ABS) for providing a Mobile IPTVservice in a mobile communication system. The ABS includes a transmitterfor periodically broadcasting a buffering data packet of broadcastbuffering content. The broadcast buffering content represents content inwhich a buffering data packet corresponding to a predetermined bufferingcapacity is periodically broadcasted, and the buffering data packetrepresents a data packet that is transmitted to be buffered in advancebefore the broadcast buffering content is actually provided to AdvancedMobile Stations (AMSs).

In accordance with further another aspect of the present invention,there is provided an Advanced Mobile Station (AMS) for providing aMobile IPTV service in a mobile communication system. The AMS includes areceiver for receiving a buffering data packet of broadcast bufferingcontent, which is periodically broadcasted. The broadcast bufferingcontent represents content in which a buffering data packetcorresponding to a predetermined buffering capacity is periodicallybroadcasted, and the buffering data packet represents a data packet thatis transmitted to be buffered in advance before the broadcast bufferingcontent is actually provided to AMSs.

In accordance with yet another aspect of the present invention, there isprovided a method for providing a Mobile IPTV service by a broadcastbase station in a mobile communication system and a broadcasting system.The method includes periodically broadcasting a buffering data packet ofbroadcast buffering content. The broadcast buffering content representscontent in which a buffering data packet corresponding to apredetermined buffering capacity is periodically broadcasted, and thebuffering data packet represents a data packet that is transmitted to bebuffered in advance before the broadcast buffering content is actuallyprovided to Advanced Mobile Stations (AMSs).

In accordance with still another aspect of the present invention, thereis provided a broadcast base station for providing a Mobile IPTV servicein a mobile communication system and a broadcasting system. Thebroadcast base station includes a transmitter for periodicallybroadcasting a buffering data packet of broadcast buffering content. Thebroadcast buffering content represents content in which a buffering datapacket corresponding to a predetermined buffering capacity isperiodically broadcasted, and the buffering data packet represents adata packet that is transmitted to be buffered in advance before thebroadcast buffering content is actually provided to Advanced MobileStations (AMSs).

BRIEF DESCRIPTION OF THE DRAWINGS

The above and other aspects, features and advantages of certainexemplary embodiments of the present invention will be more apparentfrom the following description taken in conjunction with theaccompanying drawings, in which:

FIG. 1 is a diagram schematically illustrating a process of playingcontent upon switching of content channels in a general wired IPTVsystem;

FIG. 2 is a diagram schematically illustrating configuration of an IEEE802.16m mobile communication system according to an embodiment of thepresent invention;

FIG. 3 is a flowchart illustrating a process of providing a Mobile IPTVservice by an ABS in an IEEE 802.16m mobile communication systemaccording to an embodiment of the present invention;

FIG. 4 is a flowchart illustrating a process of providing a Mobile IPTVservice by an AMS in an IEEE 802.16m mobile communication systemaccording to an embodiment of the present invention;

FIG. 5 is a diagram illustrating a structure of a frame in an IEEE802.16m mobile communication system according to an embodiment of thepresent invention;

FIG. 6 is a diagram schematically illustrating a process of providing aMobile IPTV service using a broadcast network and a mobile communicationnetwork together in an IEEE 802.16m mobile communication systemaccording to an embodiment of the present invention;

FIG. 7 is a diagram illustrating an internal structure of an ABS in anIEEE 802.16m mobile communication system according to an embodiment ofthe present invention; and

FIG. 8 is a diagram illustrating an internal structure of an AMS in anIEEE 802.16m mobile communication system according to an embodiment ofthe present invention.

Throughout the drawings, the same drawing reference numerals will beunderstood to refer to the same elements, features and structures.

DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS

Exemplary embodiments of the present invention will now be described indetail with reference to the accompanying drawings. In the followingdescription, specific details such as detailed configuration andcomponents are merely provided to assist the overall understanding ofexemplary embodiments of the present invention. Therefore, it should beapparent to those skilled in the art that various changes andmodifications of the embodiments described herein can be made withoutdeparting from the scope and spirit of the invention. In addition,descriptions of well-known functions and constructions are omitted forclarity and conciseness.

The present invention provides an apparatus and method for providing aMobile Internet Protocol TeleVision (Mobile IPTV) service in a mobilecommunication system and a broadcasting system. In addition, the presentinvention provides a Mobile IPTV service delivery apparatus and methodfor minimizing a switching time in a mobile communication system and abroadcasting system. Furthermore, the present invention provides aMobile IPTV service delivery apparatus and method for minimizing a ratioof unicast transmission in a mobile communication system and abroadcasting system. Besides, the present invention provides anapparatus and method for providing a Mobile IPTV service using abroadcast network and a mobile communication network together in amobile communication system and a broadcasting system.

An Institute of Electrical and Electronics Engineers (IEEE) 802.16mmobile communication system will be considered herein as an example ofthe mobile communication system. The Mobile IPTV service deliveryapparatus and method proposed in the present invention may be used notonly in the IEEE 802.16m mobile communication system, but also invarious other mobile communication systems, including a 3^(rd)Generation Partnership Project 2 (3GPP2) mobile communication systemusing the 3GPP2 standard based on Code Division Multiple Access (CDMA),a 3^(rd) Generation Partnership Project (3GPP) mobile communicationsystem using the 3GPP standard based on Wideband Code Division MultipleAccess (WCDMA), a Worldwide Interoperability for Microwave Access(WiMAX) mobile communication system using the WiMAX Forum NetworkWorking Group standard, and a Long Term Evolution (LTE) mobilecommunication system.

Given the following assumptions, the proposed Mobile IPTV servicedelivery apparatus and method is more effective.

In a first assumption, multicast transmission is higher in transmissionefficiency than unicast transmission, and broadcast transmission ishigher in transmission efficiency than multicast transmission.

In a second assumption, Advanced Mobile Stations (AMSs) are expected tobe smaller in content capacity than the user thermals of the wired IPTVsystems because of their limited display size.

In a third assumption, due to the continuous reduction in price ofstorage units such as flash memories, AMSs are likely to include astorage unit having a very high capacity of tens or hundreds ofgigabytes.

FIG. 2 schematically illustrates configuration of an IEEE 802.16m mobilecommunication system according to an embodiment of the presentinvention.

Referring to FIG. 2, the IEEE 802.16m mobile communication systemincludes an AMS 211, an Advanced Base Station (ABS) 213, an AccessService Network-GateWay (ASN-GW) 215, an Enhanced-Multicast/BroadcastService (E-MBS) server 217, and a content server 219.

A process of providing a Mobile IPTV service by an ABS in an IEEE802.16m mobile communication system according to an embodiment of thepresent invention will be described with reference to FIG. 3.

FIG. 3 illustrates a process of providing a Mobile IPTV service by anABS in an IEEE 802.16m mobile communication system according to anembodiment of the present invention.

Referring to FIG. 3, the ABS selects broadcast buffering contentaccording to the selection criteria predetermined by a Network ServiceProvider (NSP), in step 311. The ‘broadcast buffering content’ refers tocontent in which buffering data packets corresponding to a predeterminedbuffering capacity are periodically broadcasted by an ABS, and the‘buffering data packets’ refers to data packets that are transmitted inorder to be buffered in advance before the broadcast buffering contentis actually provided to each AMS to reduce a switching time of contentavailable in a Video-on-Demand (VoD) service.

In step 311, the NSP may determine the selection criteria such thatcontent corresponding to the top menu on a menu tree provided in theMobile IPTV service, or high-priority top-category content, such aspopular movies, drama, news, and sports, may be selected as broadcastbuffering content. The selection criteria are subject to change.

In step 313, the ABS periodically broadcasts buffering data packetscorresponding to the buffering capacity, for the selected broadcastbuffering content. The period, at which the buffering packets of theselected broadcast buffering content are broadcasted, is also subject tochange. The ABS broadcasts the buffering data packets usingmulticast/broadcast channels, or broadcasts the buffering data packetsusing idle unicast channels among unicast channels.

In step 315, the ABS determines if a content channel request is receivedfrom an arbitrary AMS. If no content channel request is received fromthe AMS, the ABS returns to step 311. However, if a content channelrequest is received from the AMS, the ABS determines in step 317 whethera content channel corresponding to the received content channel requestis a content channel playing broadcast buffering content.

If the content channel corresponding to the received content channelrequest is not a content channel playing broadcast buffering content,the ABS transmits data packets corresponding to the entire contentneeded to be provided in the content channel corresponding to thereceived content channel request, to the AMS in a unicast manner in step319.

On the other hand, if the content channel corresponding to the receivedcontent channel request is a content channel playing broadcast bufferingcontent, the ABS transmits the non-broadcasted remaining data packets inthe broadcast buffering content to the AMS in a unicast manner in step321.

Next, a process of providing a Mobile IPTV service by an AMS in an IEEE802.16m mobile communication system according to an embodiment of thepresent invention will be described with reference to FIG. 4.

FIG. 4 illustrates a process of providing a Mobile IPTV service by anAMS in an IEEE 802.16m mobile communication system according to anembodiment of the present invention.

Referring to FIG. 4, the AMS detects broadcast buffering contentinformation representing broadcast buffering content being broadcasted,using a MAP message in step 411. The MAP message will be described indetail below. In step 413, the AMS determines the presence/absence ofnon-buffered broadcast buffering content in the broadcast bufferingcontent using the broadcast buffering content information. In theabsence of the non-buffered broadcast buffering content, the AMS returnsto step 411.

However, in the presence of the non-buffered broadcast bufferingcontent, the AMS receives and buffers buffering data packets of thenon-buffered broadcast buffering content in step 415. Locationinformation of a resource region, or an E-MBS burst region, wherebuffering data packets of the broadcast buffering content aretransmitted, is included in the MAP message, and the AMS receives andbuffers buffering data packets of the non-buffered broadcast bufferingcontent in the E-MBS burst region.

In step 417, the AMS determines if a content channel request isdetected. If no content channel request is detected, the AMS returns tostep 411.

On the other hand, if a content channel request is detected, the AMSdetermines in step 419 whether a content channel corresponding to thedetected content channel request is a content channel playing broadcastbuffering content. If the content channel corresponding to the detectedcontent channel request is not a content channel playing broadcastbuffering content, the AMS transmits a content channel request for acontent channel corresponding to the detected content channel request,to an ABS in step 421, and then proceeds to step 425.

However, if the content channel corresponding to the detected contentchannel request is a content channel playing broadcast buffering contentin step 419, the AMS plays buffering data packets having been bufferedin advance for the broadcast buffering content corresponding to thecontent channel corresponding to the detected content channel request,and sends the ABS a content channel request for requesting transmissionof the remaining data packets in the broadcast buffering content in step423, and then proceeds to step 425.

In step 425, the AMS receives data packets provided in the contentchannel, from the ABS.

Continuing to receive and decode control messages such as the MAPmessage, and receiving buffering data packets of broadcast bufferingcontent in order to receive buffering data packets even when there is noneed for the remaining services other than the E-MBS service, may causeserious problems in terms of power saving of the AMS.

Therefore, information representing a transmission schedule of thebroadcast buffering content should be transmitted intermittently in thebuffering data packets. The information representing a transmissionschedule of the broadcast buffering content will be assumed to betransmitted over a content MAP message.

In this case, the AMS is allowed to receive a content MAP message onlyat the time the content MAP message is transmitted, and to receivebuffering data packets only at the transmission time of the bufferingdata packets of broadcast buffering content, which should be bufferedaccording to the transmission schedule of broadcast buffering content,included in the received content MAP message. The AMS may be notified ofthe transmission time of the content MAP message by means of a separatebroadcast message, or may be notified of the transmission time by awake-up message before the content MAP message is transmitted. Thecontent MAP message may be transmitted over an E-MBS burst region, whichwill be described below with reference to FIG. 5.

FIG. 5 illustrates a structure of a frame in an IEEE 802.16m mobilecommunication system according to an embodiment of the presentinvention.

Referring to FIG. 5, the frame includes an Advanced-MAP (A-MAP) region511, an E-MBS MAP region 515, and E-MBS burst regions 517, 519, 521, and523. The A-MAP region 511 includes an E-MBS A-MAP region 513.

The A-MAP region 511 is a region where A-MAP messages of the ABS aretransmitted, and the E-MBS A-MAP region 513 is a region where E-MBSA-MAP messages associated especially with the E-MBS service aretransmitted. Having decoded E-MBS A-MAP messages in the E-MBS A-MAPregion 513, an AMS may detect information about the E-MBS MAP region515. The E-MBS MAP region 515 is a region where an E-MBS MAP message istransmitted. The E-MBS MAP message includes resource allocationinformation for the E-MBS burst regions 517, 519, 521, and 523.

The AMS may detect resource allocation information for the E-MBS burstregions 517, 519, 521, and 523 by decoding the E-MBS MAP message, andreceives data packets in the E-MBS burst regions 517, 519, 521, and 523.

A content MAP message is transmitted over an E-MBS burst region in theform of a data packet, and uses a Connection IDentifier (CID) fortransmission of a content MAP message in order to identify whether thedata packet is a content MAP. Thus, the AMS may determine that a datapacket being transmitted using the CID for transmission of a content MAPmessage is a content MAP message.

Having received the content MAP message in the above manner, the AMS maydetect a transmission schedule of broadcast buffering content. However,an AMS, which has already stored a large amount of content, should beable to easily determine whether it will receive and buffer only some ofthe buffering data packets, or whether the AMS is not required toreceive buffering data packets being transmitted for a relevant period,because it has already received all of the necessary buffering datapackets.

Therefore, in an embodiment of the present invention, versioninformation of buffering data packets and information indicating certainfractions among the fractions that buffering data packets of the versioninclude, are included in an E-MBS MAP message or a content MAP message,allowing the AMS to easily determine the necessity of receiving thebuffering data packets without directly decoding the buffering datapackets.

For example, it is assumed that the version information of bufferingdata packets is implemented with 4 bits, a fraction IDentifier (ID) isimplemented with 8 bits, and all buffering data packets are divided into256 fractions according to the content type or the location on the menutree. In this case, if an ABS transmits a content MAP message includingthe 4-bit version information and the 8-bit fraction ID, an AMS maydetermine the necessity of receiving the buffering data packets,depending on the version information and the frame ID, making itpossible to prevent a processing load caused by the unnecessaryreception and decoding of buffering data packets.

Next, a process of providing a Mobile IPTV service using a broadcastnetwork and a mobile communication network together in an IEEE 802.16mmobile communication system according to an embodiment of the presentinvention will be described with reference to FIG. 6.

FIG. 6 schematically illustrates a process of providing a Mobile IPTVservice using a broadcast network and a mobile communication networktogether in an IEEE 802.16m mobile communication system according to anembodiment of the present invention.

Referring to FIG. 6, an AMS receives content MAP messages 611 and 619,and buffering data packets 613, 615, 617, 621, and 623 of broadcastbuffering content through a broadcast channel of a broadcast network,and buffers the received MAP messages and data packets. The broadcastingnetwork includes a broadcast base station, and the broadcast basestation transmits content MAP messages and the buffering data packets613, 615, 617, 621, and 623 of broadcast buffering content. Uponreceiving a content channel request, the AMS receives the remaining datapackets over a mobile communication network, while playing the bufferingdata packets having already been buffered, for the broadcast bufferingcontent.

Next, an internal structure of an ABS in an IEEE 802.16m mobilecommunication system according to an embodiment of the present inventionwill be described with reference to FIG. 7.

FIG. 7 illustrates an internal structure of an ABS in an IEEE 802.16mmobile communication system according to an embodiment of the presentinvention.

Referring to FIG. 7, an ABS 700 includes a receiver 711, a controller713, a transmitter 715, and a memory 717.

The controller 713 controls the overall operation of the ABS 700. Undercontrol of the controller 713, the transmitter 715 transmits the E-MBSA-MAP message, E-MBS MAP message, content MAP message, buffering datapackets of broadcast buffering content, and data packets of content, asdescribed in connection with FIGS. 3 and 5. The memory 717 buffersvarious data required for an operation of the ABS 700, and also buffersthe E-MBS A-MAP message, E-MBS MAP message, content MAP message,buffering data packets of broadcast buffering content, and data packetsof content. The receiver 711 receives a content channel request from anAMS.

While the receiver 711, the controller 713, the transmitter 715, and thememory 717 are implemented as separate units in the internal structureof the ABS 700 in FIG. 7 by way of example, the receiver 711, thecontroller 713, the transmitter 715, and the memory 717 may beimplemented in a single unit.

Although not separately illustrated, the broadcast base station includesa controller, a transmitter, and a memory. The controller controls theoverall operation of the broadcast base station. Under control of thecontroller, the transmitter transmits content MAP messages and bufferingdata packets of broadcast buffering content, and the memory buffersvarious data required for an operation of the broadcast base station,and also buffers the content MAP messages and buffering data packets ofbroadcast buffering content. Likewise, the controller, the transmitter,and the memory may be implemented as separate units, or may beimplemented in a single unit.

Next, an internal structure of an AMS in an IEEE 802.16m mobilecommunication system according to an embodiment of the present inventionwill be described with reference to FIG. 8.

FIG. 8 illustrates an internal structure of an AMS in an IEEE 802.16mmobile communication system according to an embodiment of the presentinvention.

Referring to FIG. 8, an AMS 800 includes a receiver 811, a controller813, a transmitter 815, and a memory 817.

The controller 813 controls the overall operation of the AMS 800. Undercontrol of the controller 813, the transmitter 815 transmits a contentchannel request to an ABS as described in connection with FIG. 4. Undercontrol of the controller 813, the receiver 811 receives, from the ABS,an E-MBS A-MAP message, an E-MBS MAP message, a content MAP message,buffering data packets of broadcast buffering content, and data packetsof content. The memory 817 buffers various data required for anoperation of the AMS 800, and also buffers the E-MBS A-MAP message, theE-MBS MAP message, the content MAP message, the buffering data packetsof broadcast buffering content, and the data packets of content.

While the receiver 811, the controller 813, the transmitter 815, and thememory 817 are implemented as separate units in the internal structureof the AMS 800 in FIG. 8 by way of example, the receiver 811, thecontroller 813, the transmitter 815, and the memory 817 may beimplemented in a single unit.

As is apparent from the foregoing description, the present invention mayminimize the switching time during a Mobile IPTV service in a mobilecommunication system and a broadcasting system.

In addition, the present invention may minimize a ratio of unicasttransmission during a Mobile IPTV service in a mobile communicationsystem and a broadcasting system, thereby maximizing resourceefficiency.

Besides, the present invention may provide a Mobile IPTV service using abroadcast network and a mobile communication network together in amobile communication system and a broadcasting system, therebyminimizing the amount of wireless resources used for the Mobile IPTVservice.

While the invention has been shown and described with reference tocertain exemplary embodiments thereof, it will be understood by thoseskilled in the art that various changes in form and details may be madetherein without departing from the spirit and scope of the invention asdefined by the appended claims and their equivalents.

What is claimed is:
 1. A method for providing a Mobile Internet ProtocolTeleVision (Mobile IPTV) service by an Advanced Base Station (ABS) in amobile communication system and a broadcasting system, comprising:periodically broadcasting a buffering data packet of broadcast bufferingcontent; wherein the broadcast buffering content represents content inwhich a buffering data packet corresponding to a predetermined bufferingcapacity is periodically broadcasted, and the buffering data packetrepresents a data packet that is transmitted to be buffered in advancebefore the broadcast buffering content is actually provided to AdvancedMobile Stations (AMSs).
 2. The method of claim 1, further comprising:upon receiving a content channel request from an arbitrary AMS,determining whether a content channel corresponding to the contentchannel request is a content channel included in the broadcast bufferingcontent; if the content channel corresponding to the content channelrequest is a content channel included in the broadcast bufferingcontent, transmitting, to the arbitrary AMS, remaining data packetsexcept for the buffering data packet in broadcast buffering contentbeing played in the content channel corresponding to the content channelrequest; and if the content channel corresponding to the content channelrequest is not a content channel included in the broadcast bufferingcontent, transmitting, to the arbitrary AMS, data packets correspondingto the entire content being played in the content channel correspondingto the content channel request.
 3. The method of claim 2, wherein thetransmitting remaining data packets comprises transmitting the remainingdata packets to the AMS in a unicast or multicast manner; and whereinthe transmitting data packets corresponding to the entire contentcomprises transmitting the data packets corresponding to the entirecontent to the AMS in a unicast or multicast manner.
 4. The method ofclaim 1, wherein the periodically broadcasting a buffering data packetcomprises: transmitting a control message that includes a resourceregion in which a content MAP message representing information about atransmission schedule of the buffering data packet is transmitted, andinformation needed for decoding; and transmitting the buffering datapacket in resource regions corresponding to the transmission schedule ofthe buffering data packet.
 5. A method for providing a Mobile InternetProtocol TeleVision (Mobile IPTV) service by an Advanced Mobile Station(AMS) in a mobile communication system, comprising: receiving abuffering data packet of broadcast buffering content, which isperiodically broadcasted; wherein the broadcast buffering contentrepresents content in which a buffering data packet corresponding to apredetermined buffering capacity is periodically broadcasted, and thebuffering data packet represents a data packet that is transmitted to bebuffered in advance before the broadcast buffering content is actuallyprovided to AMSs.
 6. The method of claim 5, further comprising: upondetecting a content channel request, determining whether a contentchannel corresponding to the content channel request is a channelincluded in the broadcast buffering content; if the content channelcorresponding to the content channel request is a channel included inthe broadcast buffering content, playing a buffering data packet ofbroadcast buffering content being played in the content channelcorresponding to the content channel request, and transmitting a contentchannel request for requesting transmission of remaining data packets,to an Advanced Base Station (ABS); and if the content channelcorresponding to the content channel request is not a channel includedin the broadcast buffering content, transmitting a content channelrequest for the content channel corresponding to the content channelrequest, to the ABS.
 7. The method of claim 5, wherein the receiving abuffering data packet comprises: receiving a control message thatincludes a resource region in which a content MAP message representinginformation about a transmission schedule of the buffering data packetis transmitted, and information needed for decoding; and receiving thebuffering data packet in resource regions corresponding to thetransmission schedule of the buffering data packet.
 8. The method ofclaim 5, wherein the receiving a buffering data packet comprises:detecting broadcast buffering content information including informationabout at least one of a type, a transmission schedule, a transmissionresource, and a transmission method for broadcast buffering contentbeing broadcasted by an ABS; determining whether broadcast bufferingcontent whose buffering data packet has not been buffered is present inthe broadcast buffering content being broadcasted by the ABS; and if thebroadcast buffering content whose buffering data packet has not beenbuffered is present, receiving buffering data packets of the broadcastbuffering content whose buffering data packet has not been buffered. 9.An Advanced Base Station (ABS) for providing a Mobile Internet ProtocolTeleVision (Mobile IPTV) service in a mobile communication system,comprising: a transmitter for periodically broadcasting a buffering datapacket of broadcast buffering content; wherein the broadcast bufferingcontent represents content in which a buffering data packetcorresponding to a predetermined buffering capacity is periodicallybroadcasted, and the buffering data packet represents a data packet thatis transmitted to be buffered in advance before the broadcast bufferingcontent is actually provided to Advanced Mobile Stations (AMSs).
 10. TheABS of claim 9, further comprising: a receiver for receiving a contentchannel request from an arbitrary AMS; and a controller for, determiningwhether a content channel corresponding to the content channel requestis a content channel included in the broadcast buffering content; if thecontent channel corresponding to the content channel request is acontent channel included in the broadcast buffering content, controllingthe transmitter to transmit, to the arbitrary AMS, remaining datapackets except for the buffering data packet in broadcast bufferingcontent being played in the content channel corresponding to the contentchannel request; and if the content channel corresponding to the contentchannel request is not a content channel included in the broadcastbuffering content, controlling the transmitter to transmit, to thearbitrary AMS, data packets corresponding to the entire content beingplayed in the content channel corresponding to the content channelrequest.
 11. The ABS of claim 9, wherein the transmitter transmits theremaining data packets to the AMS in a unicast or multicast manner; andthe transmitter transmits the data packets corresponding to the entirecontent to the AMS in a unicast or multicast manner.
 12. The ABS ofclaim 9, wherein the transmitter transmits a control message thatincludes a resource region in which a content MAP message representinginformation about a transmission schedule of the buffering data packetis transmitted, and information needed for decoding, and the transmittertransmits the buffering data packet in resource regions corresponding tothe transmission schedule of the buffering data packet.
 13. An AdvancedMobile Station (AMS) for providing a Mobile Internet Protocol TeleVision(Mobile IPTV) service in a mobile communication system, comprising: areceiver for receiving a buffering data packet of broadcast bufferingcontent, which is periodically broadcasted; wherein the broadcastbuffering content represents content in which a buffering data packetcorresponding to a predetermined buffering capacity is periodicallybroadcasted, and the buffering data packet represents a data packet thatis transmitted to be buffered in advance before the broadcast bufferingcontent is actually provided to AMSs.
 14. The AMS method of claim 13,further comprising: a controller for, upon detecting a content channelrequest, determining whether a content channel corresponding to thecontent channel request is a channel included in the broadcast bufferingcontent; if the content channel corresponding to the content channelrequest is a channel included in the broadcast buffering content,playing a buffering data packet of broadcast buffering content beingplayed in the content channel corresponding to the content channelrequest, and controlling a transmitter to transmit a content channelrequest for requesting transmission of remaining data packets, to anAdvanced Base Station (ABS); and if the content channel corresponding tothe content channel request is not a channel included in the broadcastbuffering content, controlling the transmitter to transmit a contentchannel request for the content channel corresponding to the contentchannel request, to the ABS.
 15. The AMS of claim 13, wherein thereceiver receives a control message that includes a resource region inwhich a content MAP message representing information about atransmission schedule of the buffering data packet is transmitted, andinformation needed for decoding, and the receiver receives the bufferingdata packet in resource regions corresponding to the transmissionschedule of the buffering data packet.
 16. The AMS of claim 13, whereinthe controller includes: detecting broadcast buffering contentinformation representing broadcast buffering content being broadcastedby an ABS; determining whether broadcast buffering content whosebuffering data packet has not been buffered is present in the broadcastbuffering content being broadcasted by the ABS; and if the broadcastbuffering content whose buffering data packet has not been buffered ispresent, controlling the receiver to receive buffering data packets ofthe broadcast buffering content whose buffering data packet has not beenbuffered.
 17. A method for providing a Mobile Internet ProtocolTeleVision (Mobile IPTV) service by a broadcast base station in a mobilecommunication system and a broadcasting system, comprising: periodicallybroadcasting a buffering data packet of broadcast buffering content;wherein the broadcast buffering content represents content in which abuffering data packet corresponding to a predetermined bufferingcapacity is periodically broadcasted, and the buffering data packetrepresents a data packet that is transmitted to be buffered in advancebefore the broadcast buffering content is actually provided to AdvancedMobile Stations (AMSs).
 18. The method of claim 17, wherein theperiodically broadcasting a buffering data packet comprises:transmitting a content MAP message representing information about atransmission schedule of the buffering data packet; and transmitting thebuffering data packet depending on the transmission schedule of thebuffing data packet.
 19. A broadcast base station for providing a MobileInternet Protocol TeleVision (Mobile IPTV) service in a mobilecommunication system and a broadcasting system, comprising: atransmitter for periodically broadcasting a buffering data packet ofbroadcast buffering content; wherein the broadcast buffering contentrepresents content in which a buffering data packet corresponding to apredetermined buffering capacity is periodically broadcasted, and thebuffering data packet represents a data packet that is transmitted to bebuffered in advance before the broadcast buffering content is actuallyprovided to Advanced Mobile Stations (AMSs).
 20. The broadcast basestation of claim 19, wherein the transmitter transmits a content MAPmessage representing information about a transmission schedule of thebuffering data packet and information needed for decoding, and thetransmitter transmits the buffering data packet depending on thetransmission schedule of the buffing data packet.